Vagina

Three Layers of Tissue

The vagina consists of three layers of tissue. The mucosa is the layer on the surface that can be touched. It consists of mucous membranes and is a surface similar to the lining of the mouth.

Unlike the smooth surface of the mouth lining, the vagina contains folds or wrinkles. The next layer of tissue is a layer of muscle, concentrated mostly around the outer third of the vagina. The third, innermost layer consists of fibrous tissue that connects to other anatomical structures.

In the sexually unstimulated state, the vagina is shaped like a flattened tube, the sides of which are collapsed on each other. It is not a continually open space, or "hole" as often thought by both women and men. It is a potential space.

Because of its muscular tissue, the vagina has the ability to expand and contract, like a balloon, allowing a baby to pass through during childbirth, or adjusting to fit snugly around a tampon, a finger or any size penis.

The internal walls of the vagina itself do not have a great supply of nerve endings, thus are not very sensitive to touch. The outer one-third of the vagina, especially near the opening, contains nearly 90 percent of the vaginal nerve endings and therefore is much more sensitive to touch than the inner two-thirds of the vaginal barrel.

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